[llvm] r173839 - [MC][COFF] Delay handling symbol aliases when writing
Michael J. Spencer
bigcheesegs at gmail.com
Tue Jan 29 14:10:07 PST 2013
Author: mspencer
Date: Tue Jan 29 16:10:07 2013
New Revision: 173839
URL: http://llvm.org/viewvc/llvm-project?rev=173839&view=rev
Log:
[MC][COFF] Delay handling symbol aliases when writing
Fixes PR14447 and PR9034. Patch by Nico Rieck!
Modified:
llvm/trunk/lib/MC/WinCOFFObjectWriter.cpp
llvm/trunk/lib/MC/WinCOFFStreamer.cpp
llvm/trunk/test/MC/COFF/symbol-alias.s
Modified: llvm/trunk/lib/MC/WinCOFFObjectWriter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/WinCOFFObjectWriter.cpp?rev=173839&r1=173838&r2=173839&view=diff
==============================================================================
--- llvm/trunk/lib/MC/WinCOFFObjectWriter.cpp (original)
+++ llvm/trunk/lib/MC/WinCOFFObjectWriter.cpp Tue Jan 29 16:10:07 2013
@@ -147,7 +147,9 @@ public:
object_t *createCOFFEntity(StringRef Name, list_t &List);
void DefineSection(MCSectionData const &SectionData);
- void DefineSymbol(MCSymbolData const &SymbolData, MCAssembler &Assembler);
+ void DefineSymbol(MCSymbol const &Symbol,
+ MCSymbolData const &SymbolData,
+ MCAssembler &Assembler);
void MakeSymbolReal(COFFSymbol &S, size_t Index);
void MakeSectionReal(COFFSection &S, size_t Number);
@@ -408,9 +410,10 @@ void WinCOFFObjectWriter::DefineSection(
/// This function takes a section data object from the assembler
/// and creates the associated COFF symbol staging object.
-void WinCOFFObjectWriter::DefineSymbol(MCSymbolData const &SymbolData,
+void WinCOFFObjectWriter::DefineSymbol(MCSymbol const &Symbol,
+ MCSymbolData const &SymbolData,
MCAssembler &Assembler) {
- COFFSymbol *coff_symbol = GetOrCreateCOFFSymbol(&SymbolData.getSymbol());
+ COFFSymbol *coff_symbol = GetOrCreateCOFFSymbol(&Symbol);
coff_symbol->Data.Type = (SymbolData.getFlags() & 0x0000FFFF) >> 0;
coff_symbol->Data.StorageClass = (SymbolData.getFlags() & 0x00FF0000) >> 16;
@@ -418,9 +421,9 @@ void WinCOFFObjectWriter::DefineSymbol(M
if (SymbolData.getFlags() & COFF::SF_WeakExternal) {
coff_symbol->Data.StorageClass = COFF::IMAGE_SYM_CLASS_WEAK_EXTERNAL;
- if (SymbolData.getSymbol().isVariable()) {
+ if (Symbol.isVariable()) {
coff_symbol->Data.StorageClass = COFF::IMAGE_SYM_CLASS_WEAK_EXTERNAL;
- const MCExpr *Value = SymbolData.getSymbol().getVariableValue();
+ const MCExpr *Value = Symbol.getVariableValue();
// FIXME: This assert message isn't very good.
assert(Value->getKind() == MCExpr::SymbolRef &&
@@ -428,10 +431,10 @@ void WinCOFFObjectWriter::DefineSymbol(M
const MCSymbolRefExpr *SymbolRef =
static_cast<const MCSymbolRefExpr *>(Value);
- coff_symbol->Other = GetOrCreateCOFFSymbol(&SymbolRef->getSymbol());
+ coff_symbol->Other = GetOrCreateCOFFSymbol(&Symbol);
} else {
std::string WeakName = std::string(".weak.")
- + SymbolData.getSymbol().getName().str()
+ + Symbol.getName().str()
+ ".default";
COFFSymbol *WeakDefault = createSymbol(WeakName);
WeakDefault->Data.SectionNumber = COFF::IMAGE_SYM_ABSOLUTE;
@@ -464,7 +467,7 @@ void WinCOFFObjectWriter::DefineSymbol(M
// Bind internal COFF symbol to MC symbol.
coff_symbol->MCData = &SymbolData;
- SymbolMap[&SymbolData.getSymbol()] = coff_symbol;
+ SymbolMap[&Symbol] = coff_symbol;
}
/// making a section real involves assigned it a number and putting
@@ -619,8 +622,11 @@ void WinCOFFObjectWriter::ExecutePostLay
for (MCAssembler::const_symbol_iterator i = Asm.symbol_begin(),
e = Asm.symbol_end(); i != e; i++) {
- if (ExportSymbol(*i, Asm))
- DefineSymbol(*i, Asm);
+ if (ExportSymbol(*i, Asm)) {
+ const MCSymbol &Alias = i->getSymbol();
+ const MCSymbol &Symbol = Alias.AliasedSymbol();
+ DefineSymbol(Alias, Asm.getSymbolData(Symbol), Asm);
+ }
}
}
Modified: llvm/trunk/lib/MC/WinCOFFStreamer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/WinCOFFStreamer.cpp?rev=173839&r1=173838&r2=173839&view=diff
==============================================================================
--- llvm/trunk/lib/MC/WinCOFFStreamer.cpp (original)
+++ llvm/trunk/lib/MC/WinCOFFStreamer.cpp Tue Jan 29 16:10:07 2013
@@ -55,7 +55,6 @@ public:
virtual void EmitDebugLabel(MCSymbol *Symbol);
virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
virtual void EmitThumbFunc(MCSymbol *Func);
- virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
virtual void EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute);
virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
virtual void BeginCOFFSymbolDef(MCSymbol const *Symbol);
@@ -201,44 +200,6 @@ void WinCOFFStreamer::EmitThumbFunc(MCSy
llvm_unreachable("not implemented");
}
-void WinCOFFStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
- assert((Symbol->isInSection()
- ? Symbol->getSection().getVariant() == MCSection::SV_COFF
- : true) && "Got non COFF section in the COFF backend!");
- // FIXME: This is all very ugly and depressing. What needs to happen here
- // depends on quite a few things that are all part of relaxation, which we
- // don't really even do.
-
- if (Value->getKind() != MCExpr::SymbolRef) {
- MCObjectStreamer::EmitAssignment(Symbol, Value);
- } else {
- // FIXME: This is a horrible way to do this :(. This should really be
- // handled after we are done with the MC* objects and immediately before
- // writing out the object file when we know exactly what the symbol should
- // look like in the coff symbol table. I'm not doing that now because the
- // COFF object writer doesn't have a clearly defined separation between MC
- // data structures, the object writers data structures, and the raw, POD,
- // data structures that get written to disk.
-
- // Copy over the aliased data.
- MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
- const MCSymbolData &RealSD = getAssembler().getOrCreateSymbolData(
- dyn_cast<const MCSymbolRefExpr>(Value)->getSymbol());
-
- // FIXME: This is particularly nasty because it breaks as soon as any data
- // members of MCSymbolData change.
- SD.CommonAlign = RealSD.CommonAlign;
- SD.CommonSize = RealSD.CommonSize;
- SD.Flags = RealSD.Flags;
- SD.Fragment = RealSD.Fragment;
- SD.Index = RealSD.Index;
- SD.IsExternal = RealSD.IsExternal;
- SD.IsPrivateExtern = RealSD.IsPrivateExtern;
- SD.Offset = RealSD.Offset;
- SD.SymbolSize = RealSD.SymbolSize;
- }
-}
-
void WinCOFFStreamer::EmitSymbolAttribute(MCSymbol *Symbol,
MCSymbolAttr Attribute) {
assert(Symbol && "Symbol must be non-null!");
Modified: llvm/trunk/test/MC/COFF/symbol-alias.s
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/COFF/symbol-alias.s?rev=173839&r1=173838&r2=173839&view=diff
==============================================================================
--- llvm/trunk/test/MC/COFF/symbol-alias.s (original)
+++ llvm/trunk/test/MC/COFF/symbol-alias.s Tue Jan 29 16:10:07 2013
@@ -23,8 +23,11 @@ _bar:
.long 0 # 0x0
+# Order is important here. Assign _bar_alias_alias before _bar_alias.
.globl _foo_alias
_foo_alias = _foo
+ .globl _bar_alias_alias
+_bar_alias_alias = _bar_alias
.globl _bar_alias
_bar_alias = _bar
@@ -52,6 +55,14 @@ _bar_alias = _bar
// CHECK-NEXT: StorageClass = [[FOO_STORAGE_CLASS]]
// CHECK-NEXT: NumberOfAuxSymbols = [[FOO_NUMBER_OF_AUX_SYMBOLS]]
+// CHECK: Name = {{_?}}bar_alias_alias
+// CHECK-NEXT: Value = [[BAR_VALUE]]
+// CHECK-NEXT: SectionNumber = [[BAR_SECTION_NUMBER]]
+// CHECK-NEXT: SimpleType = [[BAR_SIMPLE_TYPE]]
+// CHECK-NEXT: ComplexType = [[BAR_COMPLEX_TYPE]]
+// CHECK-NEXT: StorageClass = [[BAR_STORAGE_CLASS]]
+// CHECK-NEXT: NumberOfAuxSymbols = [[BAR_NUMBER_OF_AUX_SYMBOLS]]
+
// CHECK: Name = {{_?}}bar_alias
// CHECK-NEXT: Value = [[BAR_VALUE]]
// CHECK-NEXT: SectionNumber = [[BAR_SECTION_NUMBER]]
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